Inappropriate prescribing for geriatric patients can have enormous clinical and economic consequences, yet few valid studies have compared the effectiveness of alternative approaches for reducing drug therapy problems among the elderly. The major goal of the proposed study is to provide the first rigorous, systematic comparison of the effectiveness of two interventions to reduce drug therapy problems among geriatric outpatients by improving the quality of prescribing: 1) the application of a prospective computerized drug utilization review (DUR) system, and (2) ongoing clinical pharmacists' drug regimen reviews and consultations to providers. Both theory and empirical data suggest these interventions are particularly promising. The study is a 3-year, pretest/post-test controlled trial in the General Internal Medicine Practices at the University of California, San Francisco. The drug regimens of sampled patients will be assessed for the 12-month pre-intervention and the 12-month post-intervention periods. Random pairs of a 7-member physician-pharmacist review panel will independently assess the sampled cases by reviewing medications and clinical records, using an instrument tested for reliability and validity. Targeted dependent variables will measure drug therapy problems due to schedule, dosage, drug-drug interactions, therapeutic duplication, no therapy. At the end of the pre-intervention period, sampled patients will be surveyed with a validated instrument for measuring health status, an important covariate. Data will be analyzed using analysis of covariance and multiple regression techniques. The long-term goal of this research is to reduce drug therapy problems among the elderly by improving physicians' prescribing practices. Toward this goal, the following factors will be assessed for the two interventions: 1) the effectiveness of drug therapy reviews concurrent with outpatient visits; 2) the relative effectiveness of the two drug review methods; 3) their relative cost-effectiveness; 4) their acceptability to providers and patients; 5) the logistical problems of implementation; and 6) dissemination of the findings to other settings to assist in establishing drug-therapy reviews concurrent with patients' visits.